The present invention relates to a dot matrix print head provided with an electromagnetic device for actuating the print needles which is improved in its mechanical part.
It is known that in dot matrix print heads the needles are projected against the surface to be printed, in such a way as to leave on this symbols which form the print characters, by means of an electromagnetic device comprising, for each needle, a U-shape electromagnet and a striker element, the said blade, which rockably engages with its first end on the corner of one of the poles of the electromagnet, and is attracted by the other pole when the electromagnet is excited, in such a way as to strike with its second end the head of the associated print needle. Such a structure involves the fact that, when the electromagnet is not excited, the first end of the blade, under the thrust of appropriate resilient biasing means, usually constituted by a rubber ring, abuts against the associated pole so that this must be worked with high precision in that it is necessary to avoid, in this rest position of the blade, any possible interference between this and the pole on the corner of which it engages; if, in fact, interference should occur, the position of the blade would be altered and, consequently, the quality of printing would be drastically reduced.